Files
MP-SPDZ/GC/ReplicatedSecret.cpp
2019-08-06 16:56:42 +10:00

255 lines
6.7 KiB
C++

/*
* ReplicatedSecret.cpp
*
*/
#include "ReplicatedSecret.h"
#include "ReplicatedParty.h"
#include "MaliciousRepSecret.h"
#include "Protocols/MaliciousRepMC.h"
#include "MaliciousRepThread.h"
#include "Thread.h"
#include "square64.h"
#include "Protocols/Share.h"
#include "Protocols/ReplicatedMC.hpp"
#include "Protocols/Replicated.hpp"
namespace GC
{
template<class U>
int ReplicatedSecret<U>::default_length = 8 * sizeof(ReplicatedSecret<U>::value_type);
template<class U>
SwitchableOutput ReplicatedSecret<U>::out;
template<class U>
void ReplicatedSecret<U>::load(int n, const Integer& x)
{
if ((size_t)n < 8 * sizeof(x) and abs(x.get()) >= (1LL << n))
throw out_of_range("public value too long");
*this = x;
}
template<class U>
void ReplicatedSecret<U>::bitcom(Memory<U>& S, const vector<int>& regs)
{
*this = 0;
for (unsigned int i = 0; i < regs.size(); i++)
*this ^= (S[regs[i]] << i);
}
template<class U>
void ReplicatedSecret<U>::bitdec(Memory<U>& S, const vector<int>& regs) const
{
for (unsigned int i = 0; i < regs.size(); i++)
S[regs[i]] = (*this >> i) & 1;
}
template<class U>
void ReplicatedSecret<U>::load(vector<ReadAccess<U> >& accesses,
const Memory<U>& mem)
{
for (auto access : accesses)
access.dest = mem[access.address];
}
template<class U>
void ReplicatedSecret<U>::store(Memory<U>& mem,
vector<WriteAccess<U> >& accesses)
{
for (auto access : accesses)
mem[access.address] = access.source;
}
template<class U>
void ReplicatedSecret<U>::store_clear_in_dynamic(Memory<U>& mem,
const vector<ClearWriteAccess>& accesses)
{
for (auto access : accesses)
mem[access.address] = access.value;
}
template<class U>
void ReplicatedSecret<U>::inputb(Processor<U>& processor,
const vector<int>& args)
{
auto& party = ReplicatedParty<U>::s();
party.os.resize(2);
for (auto& o : party.os)
o.reset_write_head();
InputArgList a(args);
bool interactive = party.n_interactive_inputs_from_me(a) > 0;
for (auto x : a)
{
if (x.from == party.P->my_num())
{
auto& res = processor.S[x.dest];
res.prepare_input(party.os, processor.get_input(x.params, interactive), x.n_bits, party.secure_prng);
}
}
if (interactive)
cout << "Thank you" << endl;
for (int i = 0; i < 2; i++)
party.P->pass_around(party.os[i], i + 1);
for (auto x : a)
{
int from = x.from;
int n_bits = x.n_bits;
if (from != party.P->my_num())
{
auto& res = processor.S[x.dest];
res.finalize_input(party, party.os[party.P->get_offset(from) == 1], from, n_bits);
}
}
}
template<class U>
U ReplicatedSecret<U>::input(Processor<U>& processor, const InputArgs& args)
{
int from = args.from;
int n_bits = args.n_bits;
auto& party = ReplicatedParty<U>::s();
U res;
party.os.resize(2);
for (auto& o : party.os)
o.reset_write_head();
if (from == party.P->my_num())
{
res.prepare_input(party.os, processor.get_input(args.params), n_bits, party.secure_prng);
party.P->send_relative(party.os);
}
else
{
party.P->receive_player(from, party.os[0], true);
res.finalize_input(party, party.os[0], from, n_bits);
}
return res;
}
template<class U>
void ReplicatedSecret<U>::prepare_input(vector<octetStream>& os, long input, int n_bits, PRNG& secure_prng)
{
randomize_to_sum(input, secure_prng);
*this &= get_mask(n_bits);
for (int i = 0; i < 2; i++)
BitVec(get_mask(n_bits) & (*this)[i]).pack(os[i], n_bits);
}
template<class U>
void ReplicatedSecret<U>::finalize_input(Thread<U>& party, octetStream& o, int from, int n_bits)
{
int j = party.P->get_offset(from) == 2;
(*this)[j] = BitVec::unpack_new(o, n_bits);
(*this)[1 - j] = 0;
}
template<class U>
BitVec ReplicatedSecret<U>::local_mul(const ReplicatedSecret& other) const
{
return (*this)[0] * other.sum() + (*this)[1] * other[0];
}
template<class U>
void ReplicatedSecret<U>::and_(int n,
const ReplicatedSecret<U>& x,
const ReplicatedSecret<U>& y, bool repeat)
{
(void)n, (void)x, (void)y, (void)repeat;
throw runtime_error("use static method");
}
template<>
void ReplicatedSecret<SemiHonestRepSecret>::and_(Processor<SemiHonestRepSecret>& processor,
const vector<int>& args, bool repeat)
{
auto& party = Thread<SemiHonestRepSecret>::s();
assert(party.P->num_players() == 3);
processor.check_args(args, 4);
assert(party.protocol != 0);
auto& protocol = *party.protocol;
protocol.init_mul();
for (size_t i = 0; i < args.size(); i += 4)
{
int n_bits = args[i];
int left = args[i + 2];
int right = args[i + 3];
MaliciousRepSecret y_ext;
if (repeat)
y_ext = processor.S[right].extend_bit();
else
y_ext = processor.S[right];
protocol.prepare_mul(processor.S[left].mask(n_bits), y_ext.mask(n_bits), n_bits);
}
protocol.exchange();
for (size_t i = 0; i < args.size(); i += 4)
processor.S[args[i + 1]] = protocol.finalize_mul(args[i]);
}
template<>
void ReplicatedSecret<MaliciousRepSecret>::and_(
Processor<MaliciousRepSecret>& processor, const vector<int>& args,
bool repeat)
{
MaliciousRepThread::s().and_(processor, args, repeat);
}
template<class U>
void ReplicatedSecret<U>::trans(Processor<U>& processor,
int n_outputs, const vector<int>& args)
{
assert(length == 2);
for (int k = 0; k < 2; k++)
{
square64 square;
for (size_t i = n_outputs; i < args.size(); i++)
square.rows[i - n_outputs] = processor.S[args[i]][k].get();
square.transpose(args.size() - n_outputs, n_outputs);
for (int i = 0; i < n_outputs; i++)
processor.S[args[i]][k] = square.rows[i];
}
}
template<class U>
void ReplicatedSecret<U>::reveal(size_t n_bits, Clear& x)
{
(void) n_bits;
ReplicatedSecret share = *this;
vector<BitVec> opened;
auto& party = ReplicatedParty<U>::s();
party.MC->POpen_Begin(opened, {share}, *party.P);
party.MC->POpen_End(opened, {share}, *party.P);
x = IntBase(opened[0]);
}
template<>
void ReplicatedSecret<SemiHonestRepSecret>::random_bit()
{
auto& party = ReplicatedParty<SemiHonestRepSecret>::s();
*this = party.secure_prng.get_bit();
octetStream o;
(*this)[0].pack(o, 1);
party.P->pass_around(o, 1);
(*this)[1].unpack(o, 1);
}
template<>
void ReplicatedSecret<MaliciousRepSecret>::random_bit()
{
MaliciousRepSecret res;
MaliciousRepThread::s().DataF.get_one(DATA_BIT, res);
*this = res;
}
template class ReplicatedSecret<SemiHonestRepSecret>;
template class ReplicatedSecret<MaliciousRepSecret>;
}